Field
Embodiments relate to the field of semiconductor devices, and more particularly to an insulated gate bipolar transistor device.
Discussion of Related Art
An insulated gate bipolar transistor (IGBT) device is a semiconductor device having four alternating layers (P-N-P-N) that are controlled by a metal-oxide-semiconductor (MOS) gate structure. As such, an IGBT device (also referred to herein as an IGBT) may be considered as a hybrid device that has the output switching and conduction characteristics of a bipolar transistor, while being voltage-controlled as in a metal oxide semiconductor field effect transistor (MOSFET). In particular, an IGBT cell may be constructed similarly to an n-channel vertical power MOSFET (NMOS portion) where the n+ drain is replaced with a p+ collector layer, thus forming a vertical PNP bipolar junction transistor.
In operation, when an IGBT enters an OFF state, the PNP bipolar junction transistor portion (“PNP portion”) of the IGBT may be designed to pass a (clamping) current during an inductive flyback period of operation. For example, known designs for IGBTs may employ a clamp structure that turns on the NMOS portion of the IGBT in a linear mode to enable the PNP portion to pass clamping current. Turning on the NMOS in linear mode during an inductive flyback period may be very stressful on the IGBT device due to the high voltage/high current condition, and can limit the energy performance and robustness capability of the IGBT device.
It is with respect to these and other considerations, the present disclosure is provided.